The L1 hypervisor may include the IA32_TIME_STAMP_COUNTER MSR in the vmcs12 MSR VM-exit MSR-store area as a way of determining the highest TSC value that might have been observed by L2 prior to VM-exit. The current implementation does not capture a very tight bound on this value. To tighten the bound, add the IA32_TIME_STAMP_COUNTER MSR to the vmcs02 VM-exit MSR-store area whenever it appears in the vmcs12 VM-exit MSR-store area. When L0 processes the vmcs12 VM-exit MSR-store area during the emulation of an L2->L1 VM-exit, special-case the IA32_TIME_STAMP_COUNTER MSR, using the value stored in the vmcs02 VM-exit MSR-store area to derive the value to be stored in the vmcs12 VM-exit MSR-store area. v1 -> v2: - Rename function nested_vmx_get_msr_value() to nested_vmx_get_vmexit_msr_value(). - Remove unneeded tag 'Change-Id' from commit messages. Aaron Lewis (4): kvm: nested: Introduce read_and_check_msr_entry() kvm: vmx: Rename NR_AUTOLOAD_MSRS to NR_MSR_ENTRIES kvm: vmx: Rename function find_msr() to vmx_find_msr_index() KVM: nVMX: Add support for capturing highest observable L2 TSC arch/x86/kvm/vmx/nested.c | 127 ++++++++++++++++++++++++++++++++------ arch/x86/kvm/vmx/vmx.c | 14 ++--- arch/x86/kvm/vmx/vmx.h | 9 ++- 3 files changed, 122 insertions(+), 28 deletions(-) -- 2.24.0.rc1.363.gb1bccd3e3d-goog
